Machine center



FIG. 1 is a perspective view of the machine center, showing the present design.

FIG. 2 is a front view thereof.

FIG. 3 is a rear view thereof.

FIG. 4 is a left side view thereof.

FIG. 5 is a right side view thereof; and,

FIG. 6 is a top view thereof.

The broken lines in the figures are used to show portions of the machine center that form no part of the claimed design. 

CLAIM The ornamental design for a machine center, as shown and described. 